St Matthews Digital
12 March 2017
Water Use in Auckland and beyond
Raymond Chang, an environmental scientist with BECA, spoke in a Lenten series on Water about the way we use water in Auckland
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Water Use in Auckland and beyond
Thank you, Reverend for giving me the pleasure of being able to address the congregation today. Now, I had actually prepared a few notes but I'm actually going to put that aside for the moment and tell a bit of a story, my partner would call it a teachable moment because of all the water that's being raining upon us at the moment. And I wanted to talk a little bit about my involvement out in the Huddle arrangers in particular. So as I'm sure we're all aware.
The hill ranges right now, have been experiencing what some significant rainfall, and I've heard through the grapevine that there's this magic. Number of the one in 1,000 year, rainfall event. Now, that's a very big event over a very sustained period of time. That's basically overflown. The various water reservoirs that are out in the catchment over there. And as Helen was just explaining the whole, that's affected the water supply.
A in Auckland because of one of the major water treatment plants out there. The water treatment plant is run by Medicare. And basically the reason that we have to conserve water is not because there isn't enough of it but it's because that the places that they're getting the water from is have had a lot of salt stirred up as a result of the rainfall. And one of the big treatment sort of processes inside a waste, water treatment plant A sand filter. So if you have lots of silt, all of the silk clogs, the sand and then the sand gets more difficult to dislodge. So as there's lots more sand coming into the system. They can't actually keep up with Supply because they have to keep cleaning the filters. And hence why we are all sort of having to conserve water. Some people might say, why don't we just take more out of the waikato? It's kind of the same thing because it's very turbid there too.
And I suppose what I've been doing over the last few days actually is I've been out in the her no ranges. I've been working with water care and I've been working with one of one of our long-term client scampered are run by the YMCA. You may have seen them on the news on Friday and they got flooded at the same time. And one of the things that we manage quite on their behalf as the interaction with water care, releasing all the water from the dams.
And then can produce its Downstream of them. And actually, when they release more water, they tend to flood camper dare. So, you've heard that there's a range of issues in that catchment. And that's just sort of part of what I've been doing at the last little while just responding to some of that detail, so I guess.
As Helen explained, I'm an environmental manager in it an effect. And what that means is that I get quite a holistic view, a little bit more high level perhaps than some of our water Engineers are now in our team. So I don't think a lot about water and pipes too much, but I do try to help plan where they go and help decide what should happen when we need to discharge water or when we need to take water. I wanted to contextualize a Of it, the sort of global issue and then come down into what's happening nationally. And then a little bit more in the local context for Auckland as well. So I don't want to get too wrapped up in the numbers but I suppose I am a Scientist, so I do like them and I think I think I wanted to ask a question, why is water important? And everyone here today has heard a little bit about that but from my perspective water is important.
Don't because humans need it and humans need it for life. Humans are 60% water approximately and what we have right now on Earth. There's no more of it coming, so we can create a little bit of it, but in essence, it's a water cycle and we're recycling. All of the water that we are using today, I took a few more numbers from the US Geological Survey because because I like to contextualize how much water there is. So, you know, on Earth, there is one point four billion cubic kilometers. Now, no one knows what their number really looks like, but I can probably tell you that it's about 1/15 of the Moon in volume.
So that's how much water is on Earth. That's 96 percent of that is salt water.
So four percent of that 1/15 of the moon is a ten point, six million cubic kilometers. So this is all of the fresh water that we would normally take and drink and that in some sort of round number is about enough water to cover all of the US and 1 m, in and water. 1 Min today.
Now, if I took that one step further and said, how much of that is surface water, I in a river or a lake, that's fresh, that becomes 93 thousand cubic kilometers of surface water. And that's about 186 Sydney, Harbours 22 Grand Canyon's. So this is all of the water that we as humans have easy access to as on Earth.
A lot of that is also locked up in glaciers and that kind of thing. So you can see that freshwater and what we're seeing over the last week is a very, very small portion of what is readily available?
And I think we're not when I think about why we'd like water, we like water because because we need it for our food ourselves and I suppose the continuity of Our Generations as well. And I think about it into themes, kind of quality and quantity. So in terms of quantity, that's about how people can access it and what our actions can do to influence.
Once how people take it anywhere from and I think that on a global scale. This is where we are.
Really we there's a big constraint at the moment so I'm sure that a number of you, all of you will have heard some of these quotes about how the this Century's Wars are not going to be fought over oil or anything else, but they'll be fought over water and that's about accessibility to water because there are a number of Of countries out there who aren't as gifted as New Zealand, and they have real problem accessing water. It's not a new issue though. So I just wanted to sort of show that water rights, allocation and sort of access have been around for as long as we've had borders, really. So I wanted to take an example. So the Nile River itself, it comes through from mainly three different Trees. It starts in Ethiopia that flows through Sudan, and then it ends up flowing through Egypt before it ends up in the Mediterranean. And one of the ways that water allocation and quantity is managed is through International treaties.
So if I was in Ethiopia, I might be very tempted to take and all of the water that was falling on Ethiopia and keep it for myself. If I was wanting to I suppose Jane the own resource allocation for my population but there are international treaties that require Ethiopia to allow a certain volume of water down the Nile through to the next user Sudan and then again down to Egypt and this happens all across the world. So there's the Danube and Europe and there's a number of other countries that that have international treaties that require allocation to be thought of and I much Managed manner.
That's probably not a big deal to New Zealand though because we aren't surrounded by any other countries, but I suppose if you think about it in the local context, we have the similar situation. You know, I have a farmer out in Cleveland clevedon and I might want to take a certain amount of water to irrigate my paddocks, maybe not this week but but further on I may want to take it through and height of summer when I have a low flow and my river and unwanted Take that to be able to make my crops grow so that I can build up my cows that I can make more money now. In New Zealand, we managed allocation and much the same way. It's not an international treaty but it is one of those avenues that the resource management act helps us manage. And you can see that one of the big constraints in New Zealand now and going forward will be allocation. So right now in Canterbury and Bay of Plenty and waikato, we see major constraints on.
on how people can access water, what is fair use of water and and how you can actually demonstrate that you're able to still provide some environmental and sort of some of those Listen, economic well-being, is as a result of that. So, it's not, it's not just a global issue. It's a New Zealander shoe to on the wall allocation front. The other thing that I wanted to really symmetrically talk about today was water quality. So what a quality, it's not a big deal when you're thinking about getting access to water. So you need the water first and you can actually spend quite a lot of money to be able to make water drinkable or usable for your crops.
New Zealand. We don't have that problem, but we do have a problem about water quality.
Or a growing problem. Perhaps I should say, if I was least controversial, we just had a new policy statement released by the government. It's the clean Waters policy. I suppose statement that is out for consultation right now and I think you've probably heard about this quite recently. Again, very topical teachable moment. 90% of New Zealand's rivers to be swimmable by 2040, 80% to be swindled by 2030, And I think this is one of the constraints, particularly in New Zealand that we are dealing with at the moment and that's an interface between how we manage sort of the longer term use of one of these resources and how we leave it for our kids and others downgrading in the future. So you'll have heard about that and I won't give my opinion on it but It's open for consultation right now. And I think there are a few touch points that are important to think about. So the national average in New Zealand at the moment is sitting at about 70%, Rivers, swimmable. That's the river by length and essentially, they're looking for another 10% on top of that. In Auckland, that number is just under 60% is swimmable by the definition and so there's a real step change that's required in Auckland to be able to get to that swim ability. There are a number of contaminants that I probably won't go into, but there's E.coli which I'm sure everyone has heard about which is an indicator for a range of bacteriological or viruses that might affect human health. But there's also nutrients that are part of that mix. So there's some good thinking that's going on about what new zealanders would like to have in the country by a.
Date. So I guess there's some thoughts from the government about whether 20 with a 2030 as the right time and what needs to be put in place to achieve that. So I guess that's something that is out in consultation right now and worth looking at it is quite pictorial, the consultation document and so quite readable suggest you do have a look at it on the ministry's website.
Finally, I guess I wanted to bring it a little bit more to Auckland and the context. So we talked a little bit about right now and what's happening and in water now, I guess I'm sure the majority of you know, that water care is sort of the council organization that manages Water and Wastewater for Auckland. And there are some numbers that are I just want to throw out again just to show that there's major infrastructure spending going on here. That's new pipes, new treatment plants, and new ways to sort of manage water and waste water. So water cares looking at spending approximately, 50 billion dollars over the next ten years, that's essentially for what have you connections being spent over the next 10 years for Bridges 5 kilometers of Tunnels for to view?
Sections. So that times 4 is going to be spent on water infrastructure, over the next short period and the operating budget for what occurs approximately 300 million dollars a year. So this is the type of spending that I suppose you're an hour rates, go into to contribute to to sort of help manage our water or and Auckland.
The water is supplied by the waikato river and also by the And over and waitakere ranges reservoirs that I earlier spoke about. So There's some quite resilient Supply there apart from the turbidity issues that were receiving right now but the main I suppose, constraints from my perspective in Auckland on Urban streams and that's about the swim ability and it's about the contaminants that we're broadly sort of discharging into those streams.
So I think I wanted to come back to the gradual him that I just heard actually. And one of the things that I thought was really nice to hear is that there is a touch the Earth, lightly, use the Earth, gently. And I think we need to think about that when we think about water and the context of Auckland and a New Zealand in particular, I had a few words down here about how we are very inefficient. And using We have so much of it and we're quite wasteful, we take water out of rivers, we spread it on land to help a grass grow. Most of that falls through, we pick up contaminants as a result of that and it ends up in our water courses. So you know, we talked about the water cycle and the fact that it comes around again but what it does do is it makes it very difficult for us to take and use water with the same efficiency as we started with So we need to be, I think mindful as we're all here to make sure that we are.
Minimizing our water use as much as possible and encouraging ourselves and our family to really think about what efficiency of water is and to touch the Earth. Gently for I suppose, tomorrow So I'm around for a little bit more and I appreciate that. I've been a little bit all over the show today because I threw away my notes but if anyone has any questions, I'm happy to take them back to the congregation. Thanks.